1,2-polybutadiene composition stabilized with phenolic acrylates or acrylamides

ABSTRACT

IT HAS BEEN FOUND THAT UNDESIRED DETERIORATION OF 1,2POLYBUTADIENE UNDER THE INFLUENCE OF HEAT, OXYGEN, OZONE AND LIGHT CAN BE ADVANTAGEOUSLY PREVENTED NBY THE INCORPORATION INTO 1,2-POLYBUTADIENE OF A SMALL AMOUNT OF A COMPOUND REPRESEOTED BY THE FORMULA:   (4-HO,R,R&#39;&#39;-PHENYL)-CH2-X-CO-C(-R&#34;)=CH2   WHEREIN X IS A -OCH2NH-, -NH- OR -O- GROUPS, EACH OF R AND R&#39;&#39; IS AN ALKYL GROUP HAVING 1 TO 4 CARBON ATOMS AND R&#34; IS A HYDROGEN ATOM OR A METHYL GROUP.

United States Patent 3,753,943 1,2-POLYBUTADIENE COMPOSITION STABI-LIZED WITH PHENOLIC ACRYLATES OR ACRYLAMIDES Haruo Ueno, Hideo Ishikawa,and Hisawaki Hamada, Ichihara, and Takashi Watanabe, and Kunio Imamora,Tokyo, Japan, assignors to UBE Industries, Ltd., and OuchishinkoChemical Industrial Company, Tokyo, Japan No Drawing. Filed Dec. 21,1971, Ser. No. 210,596 Claims priority, application Japan, Dec. 26,1970, 45/118,731 Int. Cl. C07c 107/30 US. Cl. 26032.6 A 9 ClaimsABSTRACT OF THE DISCLOSURE It has been found that undesireddeterioration of 1,2- polybutadiene under the influence of heat, oxygen,ozone and light can be advantageously prevented by the incorporationinto 1,2-polybutadiene of a small amount of a compound represented bythe formula:

wherein X is a OCH NH, NH- or -O- group, each of R and R is an alkylgroup having 1 to 4 carbon atoms and R" is a hydrogen atom or a methylgroup.

The invention relates to the stabilization of 1,2-polybutadiene and moreparticularly, a stabilized 1,2-polybutadiene composition having thevaluable property of being stabilized against deterioration duringstoring and shaping of 1,2-polybutadiene and during use of a productmade therefrom.

It is well-known that polyolefins, polyamides and various rubber-likepolymers readily deteriorate under the influence of heat, oxygen, ozone,light and the like during storing and processing of these polymers andduring the use of products made therefrom, thereby leading todeterioration of the physical properties such as coloration, opaqueness,surface-cracking, reduction of the tensile strength and the like. Inorder to obviate these defects, many attempts have been made heretoforewhich generally involve the incorporation of a stabilizer such as amine,phenol or sulfide compounds. However, amine compounds generally color ordiscolor these polymers and result in an unattractive appearance of theproduct. Therefore, amine compounds are of no practical use andconsequently, phenol compounds and sulfide compounds are used inpractice.

However, a polymer having unsaturated side chains such as vinyl groups,for example, 1,2-polybutadiene is very unstable to heat, oxygen, etc.and therefore, even though such a conventional stabilizer isincorporated thereinto, said polymer is subjected to coloration,crosslinking or other deterioration during storing and processingthereof and during use of products made therefrom. Thus,1,2-polybutadiene can be neither satisfactorily stored nor processed andis not widely used.

It has now been found that the undesired deterioration of1,2-polybutadiene under the influence of heat, oxygen, ozone, light andthe like during storing and stabilizing amount of a compound representedby the formula;

R @cm-spo-aon, OH ii R" wherein X is a --OCH NH--, NH or --O-- group,each of R and R is an alkyl group having 1-4 carbon atoms and R" is ahydrogen atom or a methyl group.

1,2-polybutadiene to which the present invention relates meanspolybutadiene containing at least 30%, particularly at least of the1,2-structure portion such as syndiotactic 1,2-polybutadiene, isotactic1,2-po1ybutadiene, rubber-like 1,2-polybutadiene, liquid1,2-polybntadiene and the like. These may be used singly or as a mixturewith each other or with other polyolefins, e.g. polyethylene andpolypropylene.

The compound represented by the above Formula I is divisible into thefollowing three types:

wherein each of R and R is an alkyl group having 1-4 carbon atoms and R"is a hydrogen atom or a methyl group.

The compounds represented by Formula II include, for example,

acryllaminomethyl-('3,S-di-tert-butyl-4-hydroxybenzyl) e er,

acryiaminomethyl- 2-hydroxy-3 ,5 di-tert-butylb enzyl) et er,

acrylaminomethyl- (Z-hydroxy-S tert-butyl-S-methylbenzyl) ether,

acrylllaminomethyl-(3,5-dimethyl-4-hydroxybenzyl) e er,

acrylaminomethyl- (2-hydroxy-3 tert-butyl-S-ethylbenzyl) ether,

acrylaminomethyl-(3methyl-4-hydroxy-t-tert-butylbenzyl) ether,

methacrylaminomethyl-(3,5di-tert-butyl-4-hydroxybenzyl) ether,

methacrylaminomethyl-(2-hydroxy-3,S-di-tert-butylbenzyl) ether,

methacrylaminomethyl-(Z-hydroxy-3-tert-butyl-5- methylbenzyl) ether,

methacrylaminomethyl- (3,5-dimethyl-4-hydroxybenzyl) ether,

methacrylaminomethyl-(2-hydroxy-3-tert-butyl5-ethyl' benzyl) ether,

methacrylaminoemthyl- 3-methyl-4-hydroxy-S-tertbutylbenzyl) ether,

and the like.

The compounds represented by Formula IH include, for example,

(4-hydroxy-3,5-di-tert-butylbenzyl) acrylate,(2-hydroxy-3,S-di-tert-butylbenzyl) acrylate, (2-hydroxy-3-tertbutyl-5-methylbenzyl) acrylate, (4-hydroxy-3,S-di-methylbenzyl)acrylate, (2-hydroxy-3'tert butyl-S-ethylbenzyl) acrylate,(4-hydroxy-3-methyl-S-tert-butylbenzyl) acrylate,(4-bydroxy-3,S-di-tert-butylbenzyl) methacrylate,(2-hydroxy-3,S-di-tert-butylbenzyl) methacrylate,(2-hydroxy-3-tert-butyl-S-methylbenzyl) methacrylate, (4-hydroxy-3,5-di-methylbenzyl) methacrylate, (2-hydroxy-3-tert-butyl-5-ethylbenzyl)methacrylate, (4-hydroxy-3-methyl-5-tert-butylbenzyl) methacrylate,

and the like.

The compounds represented by Formula IV include, for example, 1

The compounds represented by Formulae II, III and 1V can be prepared inthe following manner:

The compounds represented by Formula II may be synthesized by adehydration reaction between dialkylhydroxybenzyl alcohol andN-methylolacrylamide or N- methylolrnethacrylamide. For example,acrylaminomethyl- (3,5-di-tert-butyl-4-hydroxybenzyl) ether may besynthesized as follows: 3,5-di-tert-butyl-4-hydroxybenzyl alcohol andN-methylolacrylamide are reacted with each other at a temperature of 55to 60 C. in a toluene medium containing p-toluenesulfonic acid ascatalyst and phenothiazine as polymerization inhibitor. The toluenelayer so formed is washed with water and separated from an aqueous layerand then, dried. Finally, after removing toluene, the residue isrecrystallized using isopropanol to recover the pure compound.

The compounds represented by Formula III may be synthesized, forexample, by a dehydration reaction between dialkylhydroxybenzyl alcoholand acrylic acid or methacrylic acid, or by a de-sodium halogenidereaction between dialkylhydroxybenzyl halide and sodium acrylate orsodium methacrylate. A lower alkyl ester of acrylic acid or methacrylicacid may be used instead of the acrylic acid or methacrylic acid in theabove reaction.

The compounds represented by Formula IV may be synthesized, for example,by a dehydration reaction between dialkylphenol and methylolacrylamideor methylolmethacrylamide, a dehydration reaction betweendialkylhydroxybenzyl alcohol and,acrylamide or methacrylamide, adehydration reaction between dialkylhydroxybenzylamine and acrylic acidor methacrylic acid, or a de-hydrogen halogenide reaction betweendialkylhydroxybenzylamine and acrylic acid halide or methacrylic acidhalide. A lower alkyl ester of acrylic acid or methacrylic acid may alsobe used instead of the acrylic acid or methacrylic acid in the abovereactions. Further, the compounds represented by Formula IV may besynthesized for example by reaction between the three compounds;dialkylphenol and acrylamide or methacrylamide and formaldehyde.

The compounds represented by the Formula I may be used singly or asmixtures thereof. Only a very small amount of the compound needs to beincorporated into 1, 2-polybutadiene in order for some benefit to beobtained. In general, at least 0.01 part by weight, based on parts byweight of 1,2-polybutadiene, of the compound should be present in theresulting stabilized composition. While there is apparently no criticalupper limit with regard to the amount of the compound to beincorporated, at most 10 parts by weight, based on 100 parts by Weightof 1,2-polybutadiene, of the compound should preferably be incorporatedbecause of cost considerations. It is preferred that the amount of thecompound to be incorporated is within the range of 0.05 to 10 parts byweight.

In the practice of the present invention, it has been found that, when acompound represented by Formula I is used together with a fatty aciddiethanolamide represented by the formula:

/OH CHzOH R-CON CH2CH2OH wherein R is an alkyl group having 8 to 20carbon atoms, the compound far more effectively stabilizes1,2-polybutadiene. Preferable fatty acid diethanolamides represented byFormula V include for example lauryl diethanolamide, palmityldiethanolamide and stearyl diethanolamide, which are generally known asa lubricant such as Dianol 300 (the main ingredient is lauryldiethanolamide, made by Daiichi Kogyo Seiyaku K. K., Japan) and ToholN-230X (the main ingredient is lauryl diethanolamide, made by TohoKagaku K. K., Japan). The amount of the fatty acid diethanolamide usedis preferably within the range of 0.05 to 10 parts by weight based on100 parts by weight of 1,2-polybutadiene. The ratio by weight of thefatty acid diethanolamide to the compound represented by Formula I ispreferably 0.2 to 5.

Further, the compounds represented by Formula I may be used togetherwith other known additives, if desired, such as a lubricant,antioxidant, ultraviolet absorber, coloration inhibitor, surface activeagent, plasticizer and the like. In general, these additives are notsubjected to heat sublimation and extraction, and cause little or nodiscoloration or contamination of 1,2-polybutadiene. The amount of theadditive used is preferably within the range of 0.05 to 10 parts byweight based on 100 parts by weight of 1,2-polybutadiene.

The particular manner whereby the compound represented by the Formula Iand the additives are incorporated into 1,2-polybutadiene is notcritical. The compound and the additives may be added in any knownmanner.

The present invention will be further illustrated with reference toexamples and comparative examples, in which all parts are parts byweight.

The degree of the deterioration, crosslinking, etc. was designated bythe maximum number of cycles achieved in a repeated shaping test whereina film was shaped from the pulverized material of a film prepared in thepreceding shaping test. The melt flow rate was determined using acommercially available melt indexer having a nozzle of 2 mm. diameter ata temperature of 230 C. and a pressure of 1.2 kg./cm. (gauge pressure).The molecular weight was determined at a temperature of C. using amembrane osmometer. The content of l,2-structure portion inpolybutadiene was determined on the tablet specimen prepared from KBrpowder and polybutadiene powder in accordance with infrared absorptionspectrum analysis technique R, Hampton; Analytical Chemistry 21, 923(1949).

EXAMPLE 1 A hundred parts of finely divided syndiotatic1,2-polybutadiene (molecular weight, 140,000) powder and 1 part of whiteacrylaminomethyl-(3,5-di-tert-butyl-4-hydroxybenzyl) ether (M.P., 92 C.)were uniformly mixed and charged into a press shaping machine. In themachine, the mixture was maintained at a temperature of 240 C. and at apressure of 200 kg./cm. (gauge pressure) for minutes and shaped into afilm thereby. After being cut into small pieces, the film was chargedinto the press forming machine and shaped into a film again under thesame conditions as above. The shaping could be repeated 6 times, butcould not be repeated 7 times.

EXAMPLE 2 The procedure of Example 1 was repeated wherein whiteacrylaminomethyl-(2-hydroxy-3,S-di-tert-butylbenzyl) ether (M.P. 117 C.)was used in place of acrylaminomethyl-(3,5-di-tert-butyl 4hydroxybenzyl) ether with all other conditions remaining the same. Themaximum number of cycles of the shaping was 5.

EXAMPLE 3 The procedure of Example 1 was repeated wherein whiteacrylaminornethyl- 2-hydroxy-3 -tertbutyl- S-methylbenzyl) ether (M.P.126 C.) was used in place of acrylaminomethyl-(3,5-di-tert-butyl 4hydroxybenzyl) ether with all other conditions remaining the same. Themaximum number of cycles of the shaping was 5.

EXAMPLE 4 The procedure of Example 1 was repeated wherein whiteacrylaminomethyl-(3,5-dimethyl-4-hydroxybenzyl) ether (M.P., 76 C.) wasused in place of acrylaminomethyl-(3,5-di-tert-butyl-4-hydroxybenzyl)ether with all other conditions remaining the same. The maximum numberof cycles of the shaping was 5.

EXAMPLE 5 The procedure of Example 1 was repeated wherein whitemethacrylaminomethyl-(3,S-di-tert-butyl-4-hydroxybenzyl) ether was usedin place of acrylaminomethyl (3,S-di-tert-butyl-4-hydroxybenzyl) etherwith all other conditions remaining the same. The maximum number ofcycles of the shaping was 6.

EXAMPLE 6 The procedure of Example 1 was repeated wherein (2-hydroxy-3-tert-butyl-S-methylbenzyl) acrylate was used in place ofacrylaminomethyl-(3,5-di-tert-butyl-4-hydroxybenzyl) ether with allother conditions remaining the same. The maximum number of cycles of theshaping was 5.

EXAMPLE 8 The procedure of Example 1 was repeated wherein (4-hydroxy-3,S-dimethylbenzyl) acrylate was used in place ofacrylaminomethyl-(3,S-di-tert-butyl-4-hydroxybenzyl) ether with allother conditions remaining the same. The maximum number of cycles of theshaping was 6.

EXAMPLE 9 The procedure of Example 1 was repeated wherein (4-hydroxy-3,S-di-tert-butylbenzyl) methacrylate was used in place ofacrylaminomethyl-(3,S-di-tert-butyl-4-hydroxybenzyl) ether with allother conditions remaining the same. The maximum number of cycles of theshaping was 6.

hydroxy-3,S-di-tert-butylbenzylamino) 6 EXAMPLE 10 EXAMPLE 11 Theprocedure of Example 1 was repeated wherein (2-hydroxy-3-tert-butyl-S-methylbenzylamino) acrylate was used in place ofacrylaminomethyl-(3,5-di-tert-butyl-4-hydroxybenzyl) ether with allother conditions remaining the same. The maximum number of cycles of theshaping was 4.

EXAMPLE 12 The procedure of Example 1 was repeated wherein (4-hydroxy-3,5-di-methylbenzylamino) acrylate was used in place ofacrylaminomethyl-(3,S-di-tert-butyl-4-hydroxybenzyl) other with allother conditions remaining the same.

EXAMPLE 1 3 COMPARATIVE EXAMPLES 1-3 The procedure of Example 1 wasrepeated wherein various compounds as listed in Table 1 were used inplace of acrylaminomethyl- 3,S-di-tert-butyl-4-hydroxybenzyl) ether,respectively, with all other conditions remaining the same. The maximumnumbers of cycles of the shaping are shown in Table 1.

TABLE 1 compound Maximum added number (parts) of cycles 12,2-methylenebis(4-methy1-6- 1 2 tert-butylphenol) 22,6-di-tert-butyl-p-methyl- 1 1 phenol. 3 2,2-methylenebis(4-methy1-6- 12 Comparative Ex. No. Compound tert-butylphenol) Plus tris(nonylphenyl)phosphite.

From a comparison between Examples 1-13 and Comparative Examples 1-3, itis evident that the stabilizers of the present invention are farsuperior to conventional stabilizers.

EXAMPLE 14 parts of finely divided syndiotactic 1,2-polybutadiene(molecular weight, 6,000) powder and 1 part of acrylaminomethyl-(3,S ditert-butyl-4-hydroxybenzyl) ether were uniformly mixed. The mixtureexhibited a melt flow rate of 36.0. The mixture was charged into a pressforming machine and then, maintained at a temperature of 240 C. and at apressure of 200 kg./cm. (gauge pressure) therein for 1 minute and shapedinto a film thereby. The film exhibited a melt flow rate of 34.0.

EXAMPLE 15 The procedure of Example 14 was repeated wherein(4-hydroxy-3,5-di-tert-butylbenzyl) acrylate was used in 7 place ofacrylaminomethyl-(3,5-di-tert-butyl-4-hydroxybenzyl) ether with allother conditions remaining the same. The melt flow rates of the mixturebefore shaping and the film after shaping were 34.0 and 33.0,respectively.

EXAMPLE 16 The procedure of Example 14 was repeated wherein2,2'-methylenebis( l-methyl-6-tert-butylphenol) was used in place ofacrylaminomethyl-(3,S-di-tert-butyl-4-hydroxybenzyl) ether with allother conditions remaining the same to prepare a film thereby. The melt=flow rate of the film could not be determined because the material didnot flow out from the nozzle due to the deterioration.

EXAMPLES 17-19 The procedure of Example 1 was repeated wherein, in placeof 100 parts of the finely divided syndiotactic 1,2- polybutadiene(molecular weight, 140,000) powder, a mixture of 70 parts of the samepowder and 30 parts of the materials as listed in Table 2 was used withall other conditions remaining the same. The maximum number of cycles ofthe shaping are shown in Table 2.

TABLE 2 Maximum Material used in addition to number Ex. No. syndiotaetie1,2-p01ybutadiene powder of cycles 17 Liquid 1,2-polybutadiene(molecular weight 8 2,000; 1,2-content, 91% 18 Di-2-ethylhexyl phthalate(plastieizer) 10 19 Polypropylene (melt; flow rate, 1.0) 6

EXAMPLES 2022 TABLE 3 Maximum Material used in addition to number Ex,No. syndiotaetie 1,2-polybutadiene powder of cycles 20 Liquid 1,2polybutadiene (molecular weight, 7

2,000; 1,2-content, 91%).

21 Di-Z-ethylhexyl phthalate (plasticizer) 9 22 Polypropylene (melt flowr te, 1.0) 6

COMPARATIVE EXAMPLE 5 The procedure of Example 17 was repeated wherein2,2-methylenebis(4-methyl-6-tert-butylphenol) was used in place ofaryla-minomethyl-(3,5-di-tert-butyll-hydroxybenzyl) ether with all otherconditions remaining the same. The maximum number of cycles of theshaping was only 3.

EXAMPLE 23 The procedure of Example 1 was repeated wherein 1 part offatty acid diethanolamide (Dianol 300 made by Daiichi Kogyo Seiyaku K.K., Japan) and 0.5 part of 3,4,5,6 dibenzo 2H 1,2 oxaphosphorine-Z-oxide8 (HCA made by Sanko Chemical K. K., Japan) were used together with 1part of acrylaminomethyl-3,S-di-tertbutyl-4-hydroxybenzyl) ether withall other conditions remaining the same. The maximum number of cycles ofthe shaping was 8. The film was pure white after being subjected toshaping 8 times.

EXAMPLE 24 The procedure of Example 6 was repeated wherein 1 part ofDianol 300 was used together with 1 part of(4-hydroxy-3,S-di-tert-butylbenzyl) acrylate with all other conditionsremaining the same. The maximum number of cycles of the shaping was 7.

EXAMPLE 25 The procedure of Example 24 was repeated wherein(4-hydroxy-3,5-di-tert-butylbenzylamino) acrylate Was used in place of(4-hydroxy-3,5-di-tert-butylbenzyl) acrylate with all other conditionsremaining the same. The maximum number of cycles of the shaping was 6.

EXAMPLE 26 The procedure of Example 6 was repeated wherein 1 part ofdianol 300 and 0.5 part of HAC was used together with 1 part of(4-hydroxy-3,S-di-tert-butylbenzyl) acrylate with all other conditionsremaining the same. The maximum number of cycles of the shaping was 7.The film was pure white after being subjected to shap ing 8 times.

What we claim is:

1. A stabilized 1,2-polybutadiene composition comprising polybutadienecontaining at least 30% of a 1,2-structure portion and a stabilizingamount of a compound represented by the formula:

wherein X is a -OCH NH-, or -0- group, each of R and R is an alkyl grouphaving 1-4 carbon atoms and R" is a hydrogen atom or a methyl group.

2. A stabilized 1,2-polybutadiene composition as claimed in claim 1wherein said polybutadiene containing at least 30% of a 1,2-structureportion is at least one member selected from the group consisting ofsyndiotactic 1,2-polybutadiene, isotactic 1,2-polybutadiene, rubber-like1,2-polybutadiene and liquid 1,2-polybutadiene.

3. A stabilized 1,2-polybutadiene composition as claimed in claim 1wherein said amount of said compound represented by the Formula I isfrom 0.01 to 10 parts by weight based on parts by weight of saidpolybutadiene containing at least 30% of a 1,2-structure portion.

4. A stabilized 1,2-p0lybutadiene composition as claimed in claim 1wherein said composition further comprises 0.05 to 10 parts by weight,based on 100 parts by weight of said polybutadiene, of a fatty aciddiethanolamide represented by the formula:

OHgCHzOH R-C ON CHzCHgOH wherein R is an alkyl group having 8 to 20carbon atoms.

5. A stabilized 1,2-polybutadiene composition as claimed in claim 1wherein said compound represented by Formula I is acrylaminomethyl-(3,5di tert-butyl-4-hydroxy benzyl) ether.

6. A stabilized 1,2-polybutadiene composition as claimed in claim 1wherein said compound represented by Formula I is(4-hydroxy-3,S-di-tert-butylbenzyl) acrylate.

7. A stabilized 1,2-polybutadiene composition as claimed in claim 1wherein said compound represented by Formula I is(4-hydroxy-3,5-di-tert-butylbenzylamino) acrylate.

9 10 8. A stabilized 1,2-polybutadiene composition as claimed 3,280,06910/ 1966 Knapp ct a1 26045 .85 in claim 1 wherein said compoundrepresented by Formula 2,478,045 8/ 1949 Hatch et a1. 260-45 .85 I is(4-hydr xy-3,S-di-tert-butylbenzyl) methacrylate, 3,651,011 3/1972Schaffhauser et a1. 26045.95 9. A stabilized 1,2-polybutadienecomposition as claimed 3,245,974 4/ 1956 Angelo 260-942 in claim 1wherein said compound represented by Formula 5 3,205,429 9/ 1965 Broyleset 260-459 I is (4-hydroxy-3,5 di tert butyl-benzylamino) th- 3,223,54512/1965 Gallaugher et a1. 117-1395 acry1ate 3,677,965 7/1972 Dexter etal. 260-459 References Cited UNITED STATES PATENTS 3,627,831 12/1971Huber-Emden 260-453 3,433,835 3/1969 Muller et a1. 260--45. 9 CL3,313,866 4/1967 Horton et a1. 26045.85 260L23.7 M, 45.85 E, 45.9 NC,45.95

DONALD E. CZAJA, Primary Examiner 10 E. R. RZUCIDLO, Assistant ExaminerUNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,753,943 Dated August 21. 1973 Haruo Ueno; Hideo Ishikawa; HisawakiHamada; Inven Tak s i Watan enio I ura It is certified that errorappears in the abOVe-identified atent .and that said Letters Patent arehereby corrected as shown below:

The name of one of the co-inventors has been incorrectly designated as"Imamora" This should be corrected to read: --Imamura Further, thereshould be included as basis for priority, Japan I Application No.89906/71 filed November 12,

Column 7, line 67: "arylamincmethyl" should read acrylaminomethyl.'

Signed and sealed this 16th da'y' of July 1971,.

(SEAL) Attest:

MCCOY M. GIBSON, JR. 0. MARSHALL DANN Attesting Officer 7 Commissionerof Patents RM PC3-1050 (10-59) USCOMM-DC scan-Poo Q ".5, GOVIINHINTPRINTING OFFICE Z ||I 0-36-3!

